Assuming equal concentrations and complete dissociation, rank these aqueous solutions by their freezing points from highest to lowest. CoCl3, NH4Cl, Li2SO4

Answers

Answer 1

Answer:

NH4Cl > Li2SO4 > CoCl3

Explanation:

Let us recall that the freezing point depression depends on the molality of the solution and the number of particles present.

Let us also recall that freezing point depression is a colligative property. It depends on the number of particles present in solution.

Usually, the more the number of particles present, the lower the freezing point. Hence, NH4Cl which has only two particles will have the highest freezing point while CoCl3 which has four particles will have the lowest freezing point.


Related Questions

A 250 mL sample of gas at 1.00 atm and has the temperature increased to and the volume increased to 500 mL. What is the new pressure

Answers

Answer:

0.53atm = P2

Explanation:

Gas at 1.00atm and 20°C. Temperature increased to 40°C...

We can solve this question using combined gas law:

P1*V1 / T1 = P2*V2 / T2

Where P is pressure, V volume and T absolute temperature of 1, initial state and 2, final state.

Compunting the values of the problem:

P1 = 1.00atm

V1 = 250mL

T1 = 20°C + 273.15 = 293.15K

P2 = ?

V2 = 500mL

T2 = 40°C + 273.15 = 313.15K

1.00atm*250mL / 293.15K = P2*500mL / 313.15K

0.53atm = P2

How many doubtful digit(s) is/are allowed in any measured quantity?
(Only 3 choices.)
A.) 1
B.) 2
C.) zero​

Answers

Answer:

zero

Explanation:

I I think one should be so accurate with measurements and experiments

I mix together 50.0 mL of 0.100 M NaIO3, 50.00 mL of 0.100 M NaOH, and 10.0 mL of 0.100 M HIO3. What is the pH of the mixture

Answers

Answer:

pH = 12.66

Explanation:

The HIO3 reacts with NaOH as follows:

HIO3 + NaOH → H2O + NaIO3

The moles of HIO3 and NaOH added are:

Moles HIO3:

0.0100L * (0.100mol / L) = 0.00100 moles HIO3

Moles NaOH:

0.05000L * (0.100mol / L) = 0.00500 moles NaOH

As moles NaOH > Moles HIO3, the moles of NaOH that remain are:

0.00500mol - 0.00100mol = 0.00400 moles NaOH.

After the reaction you will have only NaOH and NaIO3. As NaIO3 is a salt, the pH of the solution is determined by only NaOH. Its concentration is:

Moles NaOH: 0.00500 moles NaOH

Volume: 50.0mL + 50.0mL + 10.0mL = 110.0mL = 0.110L

Molarity: 0.0455M NaOH = [OH-]

pOH = -log [OH-] = 1.34

pH = 14 - pOH

pH = 12.66

pH is the measure of the hydrogen or the hydronium ion in an aqueous solution. The pH of the mixture containing sodium hydroxide is 12.66.

What is pH?

pH is the potential of the hydrogen and is given as a negative log of the hydrogen concentration in the aqueous solution.

The balanced chemical reaction can be shown as:

[tex]\rm HIO_{3} + NaOH \rightarrow H_{2}O + NaIO_{3}[/tex]

Moles of iodic acid are calculated as:

[tex]\begin{aligned} \rm moles &= \rm molarity \times volume\\\\&= 0.100 \;\rm M \times 0.0100 \;\rm L \\\\&= 0.00100\;\rm moles\end{aligned}[/tex]

Moles of sodium hydroxide are calculated as:

[tex]\begin{aligned} \rm moles &= \rm molarity \times volume\\\\&= 0.100 \;\rm M \times 0.05000 \;\rm L \\\\&= 0.00500\;\rm moles\end{aligned}[/tex]

The remaining moles of sodium hydroxide are 0.00500mol - 0.00100mol = 0.00400 moles.

The pH of the mixture will be determined by sodium hydroxide, as sodium iodate is a salt.

The molar concentration of sodium hydroxide is calculated as:

[tex]\begin{aligned} \rm M &= \rm \dfrac{moles}{volume}\\\\&= \dfrac{0.00500}{0.110}\\\\&= 0.0455 \;\rm M\end{aligned}[/tex]

pH is calculated as:

[tex]\begin{aligned} \rm pOH &= \rm -log[OH^{-}] = 1.34\\\\\rm pH &= \rm 14 - pOH\\\\\rm pH &= 12.66\end{aligned}[/tex]

Therefore, 12.66 is the pH of the mixture.

Learn more about pH here:

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Which is NOT an indicator of a chemical change?

Answers

Answer:

The choice that is not an indicator of a chemical change is "State of matter changes". More common than not, chemical reactions produce energy in the form of light or heat. Along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid).

Explanation:

If a hydrogen atom and a helium atom have the same kinetic energy:________
a. the wavelength of the hydrogen atom will be about 4 times longer than the wavelength of the helium atom.
b. the wavelength of the hydrogen atom will be about 2 times longer than the wavelength of the helium.
c. the wavelength of the hydrogen atom will be roughly equal to the wavelength of the helium atom.
d. the wavelength of the helium atom will be about 2 times longer than the wavelength of the hydrogen atom.
e. the wavelength of the helium atom will be about 4 times longer than the wavelength of the hydrogen atom.

Answers

Answer: If a hydrogen atom and a helium atom have the same kinetic energy then the wavelength of the hydrogen atom will be roughly equal to the wavelength of the helium atom.

Explanation:

The relation between energy and wavelength is as follows.

[tex]E = \frac{hc}{\lambda}\\[/tex]

This means that energy is inversely proportional to wavelength.

As it is given that energy of a hydrogen atom and a helium atom is same.

Let us assume that [tex]E_{hydrogen} = E_{helium} = E'[/tex]. Hence, relation between their wavelengths will be calculated as follows.

[tex]E_{hydrogen} = \frac{hc}{\lambda_{hydrogen}}[/tex]    ... (1)

[tex]E_{helium} = \frac{hc}{\lambda_{helium}}[/tex]         ... (2)

Equating the equations (1) and (2) as follows.

[tex]E_{hydrogen} = E_{helium} = E'\\\frac{hc}{\lambda_{hydrogen}} = \frac{hc}{\lambda_{helium}} = E'\\\lambda_{helium} = \lambda_{hydrogen} = E'[/tex]

Thus, we can conclude that if a hydrogen atom and a helium atom have the same kinetic energy then the wavelength of the hydrogen atom will be roughly equal to the wavelength of the helium atom.

A major component of gasoline is octane when octane is burned in air it chemically reacts with oxygen to produce carbon dioxide and water what mass of carbon dioxide is produced by the reaction of oxygen

Answers

gasoline is the chemical that is coming out of the air

Draw structures corresponding to the following IUPAC names:(a) (Z)-2-Ethyl-2-buten-1-ol (b) 3-Cyclohexen-1-ol(c) trans-3-Chlorocycloheptanol (d) 1,4-Pentanediol(e) 2,6-Dimethylphenol (f ) o-(2-Hydroxyethyl)phenol

Answers

Answer:

Draw structures corresponding to the following IUPAC names:(a) (Z)-2-Ethyl-2-buten-1-ol (b) 3-Cyclohexen-1-ol(c) trans-3-Chlorocycloheptanol (d) 1,4-Pentanediol(e) 2,6-Dimethylphenol (f ) o-(2-Hydroxyethyl)phenol

Explanation:

According to IUPAC rules, the name of a compound is:

Prefix+root word+suffix

1) Select the longest carbon chain and it gives the root word.

2) The substituents give the prefix.

3) The functional group gives the secondary suffix and the type of carbon chain gives the primary suffix.

The structure of the given compounds are shown below:

What is unit? Write down the units of mass, temperature and power​

Answers

Explanation:

a single thing, person, or group forming part of a whole There are 36 units in my apartment building. the least whole number : one. a fixed quantity (as of length, time, or value) used as a standard of measurement An inch is a unit of length.

mass=kilogram (kg)

temperature=kelvin

power=watt

hope it helps

stay safe healthy and happy..
A unit of measurement is a definite magnitude of a quantity, defined and adopted by convention or by law, that is used as a standard for measurement of the same kind of quantity. Any other quantity of that kind can be expressed as a multiple of the unit of measurement
Mass - kilogram ( kg )
Temperature - Kelvin
Power - watt

A beaker is filled to the 500 mL mark with alcohol. What increase in volume (in mL) does the beaker contain when the temperature changes from 5° C to 30° C? (Neglect the expansion of the beaker, evaporation of alcohol and absorption of water vapor by alcohol.) The volume coefficient of expansion γγ for alcohol = 1.12 x 10-4 K-1

Answers

Answer:

"1.4 mL" is the appropriate solution.

Explanation:

According to the question,

[tex]v_0=500[/tex][tex]\alpha =1.12\times 10^{-4}[/tex][tex]\Delta \epsilon = 25[/tex]

Now,

Increase in volume will be:

⇒ [tex]\Delta V = \alpha\times v_0\times \Delta \epsilon[/tex]

By putting the given values, we get

           [tex]=1.12\times 10^{-4}\times 500\times 25[/tex]

           [tex]=1.12\times 10^{-4}\times 12500[/tex]

           [tex]=1.4 \ mL[/tex]

Identify the possible quantitative analysis you can do using only the 28.02 g/mol as a unit factor. Select one or more:

Answers

Answer:

Calculate the moles of N2 molecules in 3.94 grams of nitrogen.

Calculate the grams of N2 in 5.03 x 1020 moles of nitrogen molecules.

Explanation:

Calculate the moles of N2 molecules in 4.73 liters of nitrogen gas. FALSE. You can't make this conversion using only the conversion factor with units of g/mol. To convert liters to moles are necessaries pressure, temperature and volume of the gas to use PV = nRT

Calculate the grams of N2 in 10.58 liters of nitrogen gas. FALSE. As explained, you need, P,V and T to find the moles of the gas. With the moles you can find the mass using the conversion factor of 28.02g/mol

Calculate the moles of N2 molecules in 3.94 grams of nitrogen. TRUE. You can find the moles of N2 as follows:

3.94g N2 * (1mol/28.02g) = 0.14 moles of N2 molecules

Calculate the grams of N2 in 5.03 x 1020 moles of nitrogen molecules. TRUE. The mass in 5.03x10²⁰ moles of nitrogen molecules is:

5.03x10²⁰ moles * (28.02g/mol) = 1.4x10²²g of nitrogen.

Liquid ethyl mercaptan, C2H6S, has a density of 0.84 g/mL. Assuming that the combustion of this compound produces only CO2 , H2O, and SO2 , what masses of each of these three products would be produced in the combustion of 3.15 mL of ethyl mercaptan

Answers

Answer:

Mass CO2 = 3.75 grams

Mass H2O = 2.30 grams

Mass SO2 = 2.73 grams

Explanation:

Step 1: Data given

Density of Liquid ethyl mercaptan, C2H6S = 0.84 g/mL

Volume of ethyl mercaptan = 3.15 mL

Step 2: The reaction

2C2H6S + 9O2 → 4CO2 + 6H2O + 2SO2

Step 3: Calculate mass of ethyl mercaptan

Mass = Volume * density

Mass ethyl mercaptan = 3.15 mL * 0.84 g/mL

Mass ethyl mercaptan = 2.646 grams

Step 4: Calculate moles ethyl mercaptan

Moles = mass / molar mass

Moles ethyl mercaptan = 2.646 grams / 62.13 g/mol

Moles ethyl mercaptan = 0.04259 moles

Step 5: Calculate moles of other products

For 2 moles ethyl mercaptan we need 9 moles O2 to produce 4 moles CO2, 6 moles H2O and 2 moles SO2

For 0.04259 moles we need 0.1917 moles O2 to produce:

2*0.04259 = 0.08518 moles CO2

3*0.04259 = 0.1278 moles H2O

1*0.04259 = 0.04259 moles SO2

Step 6: Calculate mass produced

Mass = moles * molar mass

Mass CO2 = 0.08518 moles * 44.01 g/mol

Mass CO2 = 3.75 grams

Mass H2O = 0.1278 moles * 18.02 g/mol

Mass H2O = 2.30 grams

Mass SO2 = 0.04259 moles * 64.07 g/mol

Mass SO2 = 2.73 grams

How do forces between particles in gases compare to forces in the other states of matter?​

Answers

The forces in gases are weaker than forces in solids and liquids.

Because they have more kinetic energy that overcomes the force of attraction.

what is the machine used to check melting point called?​

Answers

Answer:

Melting-point apparatus

Which one of the following molecule is planer?
a. NF3 c. PH3
b. BH3 d. NCl3​

Answers

Answer:

option a

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have a great day

Cal is titrating 57.7 mL of 0.311 M HBr with 0.304 M Ba(OH)2. How many mL of Ba(OH)2 does Cal need to add to reach the equivalence point?

Answers

Answer:

118.06 mL

Explanation:

The neutralization reaction between HBr (acid) and Ba(OH)₂ (base) is the following:

2HBr + Ba(OH)₂ → BaBr₂ + 2H₂O

According to the equation, 2 moles of HBr react with 1 mol Ba(OH)₂. Thus, at the equivalence point the moles of acid and base react completely:

2 moles HBr = 1 mol Ba(OH)₂

We can replace the moles by the product of the molar concentration (M) and volume (V):

2 x (M HBr) x (V HBr) = M Ba(OH)₂ x V Ba(OH)₂

Now, we introduce the data in the equation to calculate the volume in mL of Ba(OH)₂:

V Ba(OH)₂ = (2 x (M HBr) x (V HBr))/M Ba(OH)₂

                 = (2 x 0.311 M x 57.7 mL)/(0.304 M)

                 = 118.06 mL

Therefore, 118 mL of Ba(OH)₂ are needed.

Describe how you would prepare your assigned ester from a carboxylic acid and an alcohol. You do not need to include a detailed procedure, but you should include any necessary reagents or catalyst (solvents are not needed).

Answers

Answer:

The general preparation of esters( for example ethyl ethanoate) is through a process known as ESTERIFICATION.

Explanation:

The formation of an ester by the reaction between an alkanol and an acid is known as esterification. This reaction is extremely slow and reversible at room temperature, and is catalyzed by a high concentration of hydrogen ions.

In the preparation of one of the simpler esters known as ETHYL ETHANOATE the reactants include ethanol(an alcohol) and glacial ethanoic acid(a carboxylic acid) in the presence of concentrated tetraoxosulphate VI acid as a CATALYST. Note that, a catalyst is any substance that is able to increase the rate of a chemical reaction.

The mixture is warmed in a water bath( hot but not boiling) for about 25 minutes. The mixture is poured into a beaker partially filled with a sodium or calcium chloride to remove interacted ethanol. The ethyl ETHANOATE floats on the mixture as oily globules.

What do phase diagrams demonstrate?

Select all that apply.

how the melting and boiling points of a substance change with pressure
how much heat will increase the temperature of a gram of a substance by 1°C
the pressure and temperature conditions in which a substance exists as a liquid, solid, or gas
a comparison of the temperature of a substance to the heat absorbed over time

Answers

Answer:

this answer is for first one

Explanation:

A higher evalations, where the atmospheric pressure is much lower, the boiling point increase with increased pressure up to the critical point where the gas and liquid properties become identical

the force of attraction between non polar molecules are what (a)electrovalent bond (b)covalent bond (c)Hydrogen bond (d)Van der waals forces​

Answers

Answer:

d. van der waals force

Explanation:

Van der Waals force :

the weakest intermolecular forceand consist of dipole-dipole force and dispersion force.

Di- n- pentyl ether can be converted to 1- bromopentane by treatment with HBr through essentially a(n) ________ mechanism.

Answers

Answer:

SN1 mechanism

Explanation:

The mechanism of this reaction is shown in the image attached.

The Di- n- pentyl ether is first protonated. The CH3(CH2)4OH is now a good leaving group as shown.

The attack of the bromide ion on the cation formed completes the mechanism to yield 1- bromopentane as shown in the mechanism.

Pls pls help me me pls

Answers

Answer:

Danger

Explanation:

What are the concentrations of hydronium and hydroxide ions in a solution with pH 2.6?

Please help omg. Ive been stuck for 15 minutes​

Answers

Answer:

The concentrations of hydronium and hydroxide ions in a solution with pH 2.6 are 2.51*10⁻³ and 3.98*10⁻¹² respectively.

Explanation:

pH is a measure of the acidity or alkalinity of an aqueous solution. The pH indicates the concentration of hydrogen ions present in certain solutions. Mathematically it is defined as the opposite of the base 10 logarithm or the negative logarithm of the activity of hydrogen ions, whose equation is

pH= -log [H⁺]

So, being pH= 2.6 and replacing in the definition of pH:

2.6= -log [H⁺]

[tex][H^{+} ]=10^{-2.6}[/tex]

[H⁺]=2.51*10⁻³

pOH is a measure of the concentration of hydroxide ions (OH⁻). The sum between the pOH and the pH results in 14:

pOH + pH= 14

So, being pH= 2.6:

pOH + 2.6= 14

pOH= 14 - 2.6

pOH= 11.4

The pOH is defined as the negative logarithm of the activity of the hydroxide ions. That is, the concentration of OH⁻ ions:

pOH= - log [OH⁻]

Being pOH= 11.4 and replacing

11.4= -log [OH⁻]

[tex][OH^{-} ]=10^{-11.4}[/tex]

[OH⁻]= 3.98*10⁻¹²

The concentrations of hydronium and hydroxide ions in a solution with pH 2.6 are 2.51*10⁻³ and 3.98*10⁻¹² respectively.

What type of a liquid will have a pH value equal to 12? (1 point)
Basic
Neutral
Strong acid
Weak aci

Answers

Answer: it will be basic

pH that ranges from 0-6 are acid

pH of EXACTLY 7 is neutral

pH greater than 7 are strongly basic or base

It will be Basic

Explanation:

Anything with a pH lower then 7 is acidic, anything higher then 7 is basic, and exactly 7 is neutral. Something with a pH of 12 would be considered basic and would a a strength comparable to bleach. Below I’ve attached a chart that should help also! Learning about the pH scale can be tricky and I recommend using charts to help memorize it.

I hope this helps you! Please consider marking me the Brainliest, it’s not necessary but very much appreciated. Stay healthy and stay safe! :)

Predict the product when 2-methylbutanol is oxidised with pyridium chlorochromate in dichloromethane (PCC/CH2C12) a. CH3CH2CH(CH3)COOH b. CH3CH2CH2CH(CH3)CHO C. CH3CH2CH(CH3)CHO d. CH3CH2CH(CH3)OH 8:40 PM Type a message​

Answers

Answer:

c. CH3CH2CH(CH3)CHO

Explanation:

Hello there!

In this case, according to the process for the one-step oxidation of a primary alcohol with a moderately strong oxidizing agent like pyridinium chlorochromate (PCC), whereby an aldehyde is produced, we infer that the corresponding product will be 2-methylbutanal, which matches with the choice c. CH3CH2CH(CH3)CHO according to the following reaction:

[tex]CH_3CH_2CH(CH_3)CH_2OH\rightarrow CH_3CH_2CH(CH_3)COH[/tex]

Regards!

By how many times would you expect Al2(SO4)3 to depress the F.P of water compared to sucrose C12H22011 ?​

Answers

Answer:

By how many times would you expect Al2(SO4)3 to depress the F.P of water compared to sucrose C12H22011 ?.

Explanation:

The freezing point of a pure solvent decreases further by adding a nonvolatile solute.

This is called depression in freezing point.

When an ionic solute is dissolved then the depression in the freezing point is proportional to the number of ions present in the solution.

In aluminum sulfate, there are five ions formed as shown below:

[tex]Al_2(SO_4)_3(aq)->2Al^3^+(aq)+3SO_4^2^-(aq)[/tex]

But sucrose is a covalent compound and it does not undergo dissociation.

Hence, aluminum sulfate decreases the freezing point of water by five times compared to sucrose.

Explanation:

I need help with the practice question at the bottom. Thank you.

Answers

As the gas expands on the surrounding, work is done by the system.

Therefore, W= -279J

Absorbtion of heat,q= +216J

∆U=q+W = (216-279)J= -63J

I need help with the practice question at the bottom. Thank you.

Answers

Explanation:

For this question, we apply the equation: Q = mCp AT Where m is the mass of the substance, Cp

is its specific heat capacity and AT is the

temperature change. Q = 896 x 0.45 x (5-94)

Q = -35884.8 Joules

So about -36 kilojoules of heat is released.

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Which of the five type of equilibrium problems best applies to this question: Consider the following reaction at equilibrium. What effect will reducing the volume of the reaction mixture have on the system

Answers

Answer:

d

Explanation:

>
Which statement describes an electron?
EEEE
It has a positive charge and is located in the nucleus.
O It has a positive charge and is located in orbitals around the nucleus.
It has a negative charge and is located in the nucleus.
O It has a negative charge and is located in orbitals around the nucleus.

Answers

Answer:

It has a negative charge and is located in orbitals around the nucleus

Explanation:

The statement describes an electron is " It has a negative charge and is located in orbitals around the nucleus."

What is electron?

The electron would be a subatomic particle with a negatively one elementary charge electric charge.

What is nucleus?

Protons, that have a positive charge, as well as neutrons, which have no electrical charge, make up the nucleus. Quarks were subatomic particles that make up protons but also neutrons.

Electrons were present surrounding the atom's nucleus, in contrast to protons as well as neutrons, that are contained within the nucleus at its core. Negative electrons were drawn to the positive nucleus since the electric charges of opposite polarity attract one another.

To know more about electrons and nucleus.

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Rank each of the following gases in order of increasing urms assuming equivalent amounts and all gases are at the same temperature and pressure where 1 has the lowest urms and 4 has the highest urms.

a. Gas 1 : H2S
b. Gas: He
c. Gas 3: NF3
d. Gas 4: H2O

Answers

the answer is option c

The Urms refers to the root mean square speed of the gas. The order of increasing Urms for the gases shown in the question; NF3 < H2S < H2O < He.

What is the Urms?

The Urms refers to the root mean square speed of the gas. This is ultimately dependent on the relative molecular mass of the gases when they are maintained at the same temperature.

Now, let us look at the order of increasing Urms for the gases shown in the question; NF3 < H2S < H2O < He.

Learnmore about Urms: https://brainly.com/question/365923

An unknown weak acid with a concentration of 0.530 M has a pH of 5.600. What is the Ka of the weak acid

Answers

Answer:

Ka = 3.45x10⁻⁶

Explanation:

First we calculate [H⁺], using the given pH:

pH = -log[H⁺][H⁺] = [tex]10^{-pH}=10^{-5.6}[/tex] [H⁺] = 2.51x10⁻⁶ M

To solve this problem we can use the following formula describing a monoprotic weak acid:

[H⁺] = [tex]\sqrt{C*Ka}[/tex]

We input the data that we already know:

2.51x10⁻⁶ = [tex]\sqrt{0.530*Ka}[/tex]

And solve for Ka:

Ka = 3.45x10⁻⁶
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